docs: dma-api: remove remnants of PCI DMA API

The wording sometimes suggests there are multiple functions for an
operation. This was in fact the case before PCI DMA API was removed, but
since there is only one API now, the documentation has become confusing.

To improve readability:

* Remove implicit references to the PCI DMA API (plurals, use of "both",
  etc.)

* Where possible, refer to an actual function rather than a more generic
  description of the operation.

Signed-off-by: Petr Tesarik <ptesarik@suse.com>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250627101015.1600042-4-ptesarik@suse.com

diff --git a/Documentation/core-api/dma-api.rst b/Documentation/core-api/dma-api.rst
index 0e794abdbe496fd6fed1fbd12c0c8952fd88b17f..751999a1da0bee8ae1327fb4b48ecc0bb2e18cc2 100644 (file)
--- a/Documentation/core-api/dma-api.rst
+++ b/Documentation/core-api/dma-api.rst
@@ -53,10 +53,9 @@ minimum allocation length may be as big as a page, so you should
 consolidate your requests for coherent memory as much as possible.
 The simplest way to do that is to use the dma_pool calls (see below).
 
-The flag parameter (dma_alloc_coherent() only) allows the caller to
-specify the ``GFP_`` flags (see kmalloc()) for the allocation (the
-implementation may choose to ignore flags that affect the location of
-the returned memory, like GFP_DMA).
+The flag parameter allows the caller to specify the ``GFP_`` flags (see
+kmalloc()) for the allocation (the implementation may ignore flags that affect
+the location of the returned memory, like GFP_DMA).
 
 ::
 
@@ -64,13 +63,12 @@ the returned memory, like GFP_DMA).
        dma_free_coherent(struct device *dev, size_t size, void *cpu_addr,
                          dma_addr_t dma_handle)
 
-Free a region of coherent memory you previously allocated.  dev,
-size and dma_handle must all be the same as those passed into
-dma_alloc_coherent().  cpu_addr must be the virtual address returned by
-the dma_alloc_coherent().
+Free a previously allocated region of coherent memory.  dev, size and dma_handle
+must all be the same as those passed into dma_alloc_coherent().  cpu_addr must
+be the virtual address returned by dma_alloc_coherent().
 
-Note that unlike their sibling allocation calls, these routines
-may only be called with IRQs enabled.
+Note that unlike the sibling allocation call, this routine may only be called
+with IRQs enabled.
 
 
 Part Ib - Using small DMA-coherent buffers
@@ -246,9 +244,7 @@ Part Id - Streaming DMA mappings
 Maps a piece of processor virtual memory so it can be accessed by the
 device and returns the DMA address of the memory.
 
-The direction for both APIs may be converted freely by casting.
-However the DMA API uses a strongly typed enumerator for its
-direction:
+The DMA API uses a strongly typed enumerator for its direction:
 
 ======================= =============================================
 DMA_NONE               no direction (used for debugging)
@@ -325,8 +321,7 @@ DMA_BIDIRECTIONAL   direction isn't known
                         enum dma_data_direction direction)
 
 Unmaps the region previously mapped.  All the parameters passed in
-must be identical to those passed in (and returned) by the mapping
-API.
+must be identical to those passed to (and returned by) dma_map_single().
 
 ::